Nano-sized propellers that will make it possible to deliver drugs directly to cells and even inside them using a relatively weak magnetic field have been developed by researchers at Haifa’s Technion-Israel Institute of Technology and at the Max Planck Institute for Intelligent Systems in Stuttgart, Germany.
They may be most effective getting cancer drugs into tumor cells to destroy them without harming healthy cells and tissues.
The scientists, whose research has just been published in the journal ACS Nano, said that human tissue and biological fluids are “complex visco-elastic media with ananoporous macromolecular structure. Here, we demonstrated that helical nano-propellers can be controllably steered through such a biological gel.”
The screw-like propellers have a filament diameter of about 70 nanometers and are smaller than any previously reported nano-propellers as well as any swimming microorganism.
A nanometer is one-millionth of a meter.
Prof. Alex Leshansky of the chemical engineering faculty at the Technion said that the minuscule “screw propellers” look like the tails of bacteria that propel them through bodily fluids. They are able to control movement of the nano-propellers more easily through gels, but also through liquids.
The Israeli researchers, said Leshansky, worked on the theory, while the German team concentrated on creating the tiny devices, on which they hold a patent. It will take some time, however, until the technology is used in medicine.
“The screw is the shape of the device that pulls corks out of bottles,” Leshansky said.
An exterior, weak magnetic force – which will not harm the body – is used on the outside and can move the propeller inside.